Connaught went into administration in September with the loss of more than 1,000 jobs. Photograph: PA

The UK accounting regulator is to investigate PricewaterhouseCoopers and other accountants associated with the collapse of social housing repair specialist Connaught.

The Accountancy and Actuarial Discipline Board, which can deliver unlimited fines, said it would look at the conduct of auditors PwC and of other qualified accountants in relation to Connaught's 2009 accounts and interim figures from earlier this year. The firm went into administration in September with the loss of more than 1,000 jobs.

The probe is likely to look closely at the issue of "mobilisation costs", incurred at the start of a contract. Connaught was reckoned to have a more aggressive accounting method for dealing with the costs. Some companies recognise the upfront costs immediately in their profit and loss accounts, while others spread them out over the lifetime of the contract.

The AADB declined to say what exactly it would look at, and would not name the other accountants under investigation. The inquiry is likely to extend further since PwC did not audit the interim figures.

Connaught's finance director from 2006 until its collapse was Stephen Hill, a chartered accountant. The lead audit partner on the Connaught audit in 2009 was Stephen Harrison, who retired in the summer, according to reports.

PwC said: "We will be co-operating fully with the AADB investigation and we have no further comment at this stage."